Lifting jack



Nov. 8, 1938.

F. L. GCRMLEYy LIFTING JACK Filed Dec. 14, l957 4 sheets-sheet 1 Nov. 8,1938. F. L.. GORMLEY LIFTING JACK 4 Sheets-Sheet 2 Filed DeC. 14, 1957Invenar:

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5f a s ,Frankl Go Nov., A8, l191%. F. L. GORMLEY LIFTING JACK Filed Dec.14, 1937 I Jllllllllllllllll IIIIII II'IIIIII Nov. s, 193s. F, GO'RMLEY2,135,938

LIFTING JACK Filed Dec. 14, 1957 4 sheets-sheet 4 'q'gl. A Flg.InvcnZ'o-r: E'ank L Gormley,

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Patented Nov. 8, 1938 UNITED STATES LIFTING JACK Frank L. Gormley,

The Buda Company, of Illinois Application December 14,

A18 Claims.

. 'This invention relates to ratchet lifting jacks and particularly tothat `class known as automatic lowering jacks and which have two springcontrolled pawls one for lifting the load and the other for holding theram in raised position while the lifting pawl ismoving downwardly intoposition preparatory to another lifting operation.

One of the principal objects of the present invention is to produce asimple and effective device which is adapted to automatically change thedirect operation of both the lifting and holding paw-ls from raising tolowering position or vice versa.

Another object of the invention is to have the jack so designed that theautomatic device will be located in plain'sight of the operator and sodistinctly marked asvto indicate the proper direction of movement of thereversing device for raising and lowering of the ram.

A further object of the invention is to construct the jack sothat thelifting pawl and holding pawl will be of the same size andinterchangeable with each other, thus bringing about considerablereduction in, the cost of manufacture and reduce the number or" serviceparts.

And another object of the invention is to so construct the jack thatthree of its sides will have no obstruction thereon to prevent the useof a load lifting chain on either one of the three sides.

These objects are attained by the mechanism illustrated intheaccompanying drawings.

For the purpose of illustrating the invention, one preferred formthereof is illustrated in the drawings, this vform having been found togive satisfactory and reliable results, although it is to be understoodthat the various instrumentalities of which the invention consists canbe variously arranged and organized, and the invention is not limited tothe precise arrangement and organization of these instrumentalities asherein shown and described except as required by the scope of theappended claims.

Of the drawings:

Figure 1 represents an elevation partly in section of a lifting jackembodying the principles of the present invention, the various partsthereof being in position for lowering the load.

Figure 2 represents a similar elevation partly in section showing theupper end of said lifting jack with the various parts in position forraising the load.

Figure 3 represents an elevation partly in section of the opposite sideof said lifting jack.

Figure 4l represents an elevation of the two Brookline, Mass., assignorto Harvey, Ill., a corporation 1937, Serial No. 179,669

pawls of the jack and showing the means for normally moving them abouttheir pivots into contact with the teeth oi the rack or ram.

Figure 5 represents a horizontal section of the jack on line 5, 5 onFig. 3.

Figure 6 represents a horizontal section of the jacken line 6, 6 on Fig.3.

Figure I represents a horizontal section of the jack on line `I, 1 onFig. 3.

Figure 8 represents the plan oi a portion of the upper end of thelifting jack showing the reversing shaft and the locking lever securedthereto in the position assumed when the jack is raising the load.

Figure 9 represents a similar view with the locking lever in theposition it assumes when the jack is lowering the load.

Figure l0 is an enlarged section of the reversing mechanism in theposition assumed when the load is being lowered.

Figure 11 is a section of the same on line II, II on Fig. 10.

Figure l2 is an elevation of a modified form of the yielding memberadapted to connect the projections on the two pivoted pawls when theload is being lowered, and

Figure 13 represents a side elevation of the same.

Similar characters indicate like parts throughout the several gures ofthe drawings. 30 In the drawings, I0 is the base of the jack and thisbase has extending upwardly therefrom a hollow casing II, from the upperend of which projects a handle I2 by which the jack may be carried fromplace to place. 35

As shown at IIa: the casing II is open at the front to give access tothe operating mechanism.

This casing Il is provided at the top with a square bearing I3 throughwhich extends the rectangular ram or rack I4, this rack having on thefront side thereof a plurality of teeth I5.

The ram or rack I4 has secured to its upper end a supporting head I6 andat its lower end has formed integral therewith and projecting rearwardlytherefrom another supporting member Il. Either the head I6 or theprojection I1 may be used to support a load.

The projecting member I1 extends through a slot I8 in the rear wall I9of the casing II.

The lower rear face of the ram I4 contacts with the lower inner face ofthis wall I9 as it reciprocates endwise therein, the teeth I5 of saidram being free from contact with the opposite wall 2l] of said casingIl.

Ribs I 53s contact with the opposite side walls of the ram I4 andprevent any lateral movement of the same during its endwise movement.

The ram I4 may be inserted through an opening 2l in the base II) andafter such insertion the head I3 is secured to the upper end of the ramby means of the pin 22.

The opposite side walls of the casing II have openings therein toreceive the oppositely disposed cup-shaped members 23 held in the sidewalls cf the casing I I by set screws 23x.

Disposed within these cup-shaped members 23 are trunnicns 24 projectingfrom the opposite sides of a member 25 provided with sockets 2511:either of which is adapted to receive an actuating lever 251 wherebysaid member 25 may be moved in either direction about the axis of saidtrunnions 24.

The walls of the casing II are so constructed that the trunnions 24 bedisposed ever the ends thereof and form bearings therefor.

The inner end of the socketed member 25 is provided with asemi-cylindrical seat 25 to receive the cylindrical hub 21 of a liftingpawl 23 and one wall of said inner end is cut away as at 23x to permitthe insertion of the pawl 28 from one side of the socketed member 25with its cylindrical h`ub 21 disposed in the seat 2B.

The wall on the opposite side of the socketed member 25 is provided witha cylindrical bearing 21x to receive one end of the hub 21.

The pawl 28 is adapted to oscillate about the axis of hub 21 and at itsupper end is provided with a plurality of teeth 29 adapted talengage theteeth i of the ram or rack I4.

Near the upper end of the casing II and integral therewith is a concavedseat 39 closed at one end by plate 39m.

Extending inwardly from the opposite end of said seat is a tubularmember 3 I, a portion of the wall of which is cut away to permit theoscillation therein of the hub 32, the upper end of which has formedthereon a plurality of teeth 33 adapted to engage the teeth l5 of theram or rack I4 and prevent the accidental lowering of the ram or rackI4.

The member 3l is held in position by means of a set screw 35 I.

To one side wall of the casing II is secured a headed stud 39 aboutwhich is coiled a spring 40.

One end of this spring 4B coacts with a side extension 4I formed uponthe lifting pawl 28 while the opposite end of said spring coacts with asimilar projection 4I.r on one side of the holding pawl 32, the tensionof said spring 40 being such as to cause the ends thereof to spring awayfrom each other.

The same spring 49 therefore tends, under normal conditions, to forcethe teeth of both of the pawls 28 and 32 into engagement with the teethi5 of the ram or rack I4.

The socketed member 25 is provided with a downward projection 42 whichis adapted to engage the shoulder d3 on the casing I I to limit thedownward movement of said member, and another shoulder 43 on the casingI I limits the upward movement of said member 25.

The two sockets 25.1': are provided in order that different leveragesmay be obtained in the operation of the jack under varying conditions.

When the member 25 is moved downwardly under certain conditions thelifting pawl will raise the ram or rack I4, the holding pawl 32 beingmay be moved into posi-Y tion so that the cup-shaped members 23 mayVtension 50 forming a part 3M: of the holding pawl forced outwardly fromengagement with the rack teeth I 5 against the tension of the spring 40,while the rack teeth I5 are passing the teeth 33 of said holding pawl32.

As soon as the member 25 has reached the end of any of its downwardmovements, the spring 40 will force the teeth 33 of the holding pawl 32into engagement with the rack teeth I5 and retain the rack I4 inposition while the pawl 28 is being moved downwardly into a lowerposition preparatory to another lifting operation.

This is of considerable importance as with this Vtype of jack there hasalways been a tendency for the holding and lifting pawls 28, 32 to ilyout of contact with the rack teeth I5 and allow said rack I4 and theload supported thereby to accidentally lower and thus cause seriousaccidents.

By providing a single spring 40 in the manner sho-wn and described bothof the pawls 28, 32 at all times are retained in position to engage withthe rack teeth I5 when, jack, it is necessary for the teeth of eitherpawl 28, 32 to engage the teeth I5 of the ram I4.

'I'he liftingV pawl 28 and the holding pawl 32 are exactly alike andeither one may be used in place of the other. This reduces the cost ofmanufacture to some exten The lifting pawl 28 and the holding pawl 32are both fulcrumed at their lower ends and extend upwardly from saidfulcrums with the teeth 29 and 33 at the upper ends thereof.

The pawls 28 and 32 have arms 44, 45 extending rearwardly from one sidethereof.

The arm 44 on the lifting pawl 28 has a lateral trunnion or projection46 on which is mounted an annular member 41 having a radial extension48, the periphery of which is groovedY to receive one end of a yieldinghelical spring 49.

The opposite end of this spring 49 is coiled about a helical groove inthe periphery of an exof and extending downwardly from a U-shaped block5I having a flat sided notch 5Irc therein, said block 5I being providedwith a slotted upward extensionl 52 which encloses a reversing shaft 53.

'Ihe arm 45 on pawl 32 is provided with a lateral trunnion or projection45x which is adapted to be disposed in the notch 5I1r when a load isbeing lowered.

The shaft 53 is rotatable in an elongated bearing 54 formedV in thecasing I I and has secured to the outer end thereof an actuating `wingor lever 55 by which said shaft 53 may be rotated part way about itsaxis and also under certain conditions moved forwardly and then lockedin its forward position by means to be described hereinafter.

The opposite or rear end of the reversing shaft 53 has a collar 56secured thereto between which and the slotted extension 52 is a helicalbuffer spring 56x and between the rear end of the bearing 54 and theslotted extension 52 is a longer expansible spring 51 coiled about thereversing shaft 53, said spring 51 being adapted to be expandedduring'the lowering of the load. When raising the load by theoscillation of the socketed member 25 with the teeth 29 of the pawl 28in engagement with the teeth I5 of the rack or ram I4, the spring 51will be'under compression and the wing 55 locked from turning, theslotted extension 52 at this time freely reciprocating vertically whileenclosing the reversing shaft 53 without performing any operation.

When it is desired to reverse the movements of the lifting pawl 28 andholding pawl 52 prein the operation of the,

is f

l from engagement with the inclined locking notch 55|.

When thus unlocked 'the spring 51 is :free to expand .and its expansionwill move vthe shaft 53 to .the rear and at the same time said expansionof :said lspring acting on the vslotted end 52 will nove the yieldingmember 49 into Ithe position shownfin Fig. l with the projection 45.1,'disposed inthe notch v|x, thus causing the pawls 28,132 to .beyieldinglyconnected together.

When the cam member 55x `of the wing 55 is engaged with shoulder 55|vthe reversing shaft 53 will be prevented from any movement in la rear-Ward direction and the rspring will be kept under compression untilreleased.

When in the operation -of `the jack .it is desired to lower the load,Athe spring51 is permitted to expand and cause the extension 45m on thehold ing pawl 32 to enter the notch 5|:1: in block 5I, the spring 51under expansion causing the spring 49 and its associated parts to moveabout its fulcrum 46 so vrthat the extension 45m willbe retained inthenotch 5m,` of the U-shaped block 5I during the lowering of the load.

When this has been accomplished it is obvious that 'thelifting pawl 28and the vholding pawl 32 will'be connected together through theexpansible spring v49 and the elements connected thereto, therebypermitting these pawls to operate alternately as holding pawls.

When the load `is being raised the reversing spring 49 will be in theposition indicated in Fig. 2 of thevdrawings, the lower end of saidspring being connected to the projection 46 on the lifting pawl28.

This reversing spring 49 is movable with the lifting pawl '28 and when aload is being raised floats freely in an upward and downward direction,the upper endthereof moving transversely of and being guided by thereversing shaft 53.

At this 'time the projection 45a.' of pawl 32 will befdisconnected fromythe U-shaped block 5I and the pawls 28, 32 will be disconnected fromeach other.

When Ait is desired to lower the load the reversring shaft wing 55 onthe front side of jack is placed in position to permit the movement ofthe shaft 53 to the rear into the position shown in Fig. 1.

'This rearward movement will be effected by the expansion of the spring51, which in its expansion will force the yielding reversing spring 49into position to connect together both pawls 28, 32 preparatory tolowering the load.

Thediameter of the projection 445st is somewhat lessthan'the width ofnotch 5Ix so that there is some lost motion between the' two.

vOn the upward stroke of the socketed member 25 the reversing spring `49will be drawndownwardand the surface A of the notch 5| :c in theU-shaped block y5| connected to the reversing spring 49 will come incontact with the projection 45a.` of the holding pawl 32.

The upward stroke of the socketed member 25 willthen continue untilsufficient tension has been placed'on the reversing spring 49 todisengage the lifting pawl t28 from teeth I5 in the rack bar I4.

The socketed member 25 will then be operated inla'idownwarddirection andwhile being operated in this direction the reversing spring 49 will be'raised andthe surface :C ofthe lil-shaped block 5| will "come intovcontact with the :lower .side :fof the projection 45a: on the holding:pawl "32.

This vdownward Vstroke of 'the vsocketed member 25 will lcontinue iuntilvsufficient tension .has been placed on the Areversing spring49`to1disengagethe holding pawl 32 from the teeth vI5 in the rack barI4.

After the holding pawl 32 has 4been releasedfrom the teeth `I 5 in therack bar `If4,` the socketed member 25 will be operated 'in the upwarddirection, thus allowing the load to lower until Lthe holding pawl 32contacts with another "toothfin the rack bar I4.

The lowering of the load in this :manner may continue so long as the:reversing shaftwng l55 is in .its unlocked position and the1socketed-member 25 is operated in an upward 4and downward direction.

In lifting jacks of thischarac'ter two pawls are always utilized, onebeing a :lifting pawl '.28 to raise a load, while the other such 'as 32*is the holding vpawl to hold the load during the `raising operation.

In the present device when lowering the .load the operation ofthe pawl'28 may be Vreversed so that it .may act as a holding pawl while thepawl 32 is being movedinto a new position preparatory to a furtherengagement with 'the kteeth I5 o'f ram I4.

In the present device the'pawl 28 fknown as 4the lifting pawl isconnected to and operatedby ythe socketed member 25 fulcrumed on the.main jack frame or casing while 'the fulcrum of the 'other pawl 32 orholding pawl is mounted in a tubular member 3| disposedon aaseat 30which is a part of'said main frame or casing.

When the jack is used to raise a .load the lifting pawl 28 is operatedby the socketed member 25 and will raise the'rack bar v'I4 fa certain-distance, this distance depending on 'how Amuch off center the fulcrum2:1 of vthe lifting pawl 28 -is located from the fulcrum center -23 ofthe'so'cketed member 25.

The rack bar |4 is raised in this lmanner so that the teeth I5 will passover the 'teeth `33 of the holding pawl 32.

This holding pawl 32 will hold Ithe load while another upward stroke ofthe socketedmember25 is being made, v.preparatory to further lifting ofthe load.

When the load is to be lowered Vthe reversing leverf55 is turned4clockwise to disengage vthe cam member 55a: from the locking notch 55|y-so that the lifting pawl 28 and holding'pawl 32 will lbe connectedtogether and the operation of the lifting pawl 28 will ybe reversed,said pawl 28 Aacting as an additional holding pawl while v'the load isbeing lowered.

Obviously, it is quite necessary for the lifting pawl 28 to move upwardclear of the rack teeth |.5 while the holding pawl 3-2 supports theload.

Near the end of its .upward travel vthe lifting pawl 28 will engage therack teeth I5 and raise the rack I4 sufciently to release .the `loadfrom the holding pawl 32.

The holding pawl 3.2 `will then move Aclear of the rack teeth and allowthe load `to be lowered while supported by the lifting pawl 28, whichyis being moved by the socketed member 2.5.

The holding pawl -28 will comezintoiproper position to hold the loadwhen the .requireddis'tance downwardly of the rack I4 has vbeen.reachediin the lowering operation.

This .operation :may be repeated :by .-operating the socketed member 25until the load has been lowered the requireddistance.

After this has been accomplished, by turning the reversingl lever 55into its locked position with spring 51 compressed and then operatingthe socketed member 25 as previously stated, the pawls 28 and 32 will bedisconnected and operate inthe usual manner to raise the load.

The casing has an opening 58 extending therethrough to form a handle bywhich the jack lmay be moved from place to place.

When the two pawls 28 and 32 have been connected in the mannerdescribed, the load may be automatically lowered.

In the present jack the control for reversing the operation of the pawlsis located at the front of the jack wherey it can be plainly seen andthis control is also plainly marked so that the operator can tell injust what direction the ram i4 will operate either in raising orlowering a load, thereby avoiding accidents in operating. Y

It will be noted that in the present device the load may be raised orlowered on three sides of the jack by using chain lifts if necessarywithout any obstruction from the side of the jack to prevent the raisingor lowering of the load.

In lifting by chains the. links of the chains are disposed in the slotsS0 of head I6.

The casing Il is provided on one side with an arcuate flange Bipartially surrounding the lever or wing 55 and preventing it from beingmoved accidentally.

The spring 49, block 5I Yand member 41 form a yielding connectionbetween the pawls 28 and 32 during the lowering of the load.

If desired, the yielding connection may be made of a single wire 62 ofspring steel as shown in Figs. 12 and 13.

This modified form of yielding connection has at its lower end a loop41:1: through. which the projection 46 of pawl 28 extends and near itsyupper end is bent U-shaped as at 55x to form a notch 4|:c to receive theprojection 45:6 of the holding pawl 32.

Between the loop 47x and notch 5|:c the wire 62 has coils 49:12 thereinforming a yielding spring connection between said loop 41:1: and notchedportion 40a'.

Above the notched portion 40x the wire 62 extends upwardly anddownwardly over the reversing shaft 53 as indicated at 52x.

This upward extension 52:1: straddles the shaft 53 and is movabletransversely thereof between the springs 56x and 51.

Opposite the yielding member 49 or 62, the casing I I has an opening 63in one wall thereof normally closed by a plate 63a: which may he removedto give access to said yielding member.

It is believed that the operation and many advantages of the inventionwill be understood without further description.

Having thus described my invention, I claim:

-1. A ratchet lifting jack consisting of a vertically movable rackhaving a plurality of rack teeth; a lifting pawl; a holding pawl; meansfor oscillating said lifting pawl; a yielding member supported on saidlifting pawl and movable therewith; and means for connecting the upperend of said yielding member to the holding pawl preparatory to thelowering of the load.

2. A lifting jack as set forth in claim 1 in which the lifting pawl andthe holding pawl are alike and interchangeable.

3. A lifting jack as set forth in claim 1 in which said yielding memberincludes a U-shaped block; a projection on the holding-pawl adapted tocoact with said U-shaped block; and means for retaining said projectionin the notch of said block during the lowering of the load.

4. A lifting jack as set forth in claim 1 in which said yielding memberincludes a U-shaped block; a projection on said holding pawl adapted toCoact with'said Lil-shaped block; and spring controlled mechanism forretaining said projection in the notch of said block during the loweringof the load. 1

5. A lifting jack as set forth in claim l in which the yielding memberis formed of a single wire having a loop at one end adapted to coactwith the lifting pawl, a notch to ooact with a projection on the holdingpawl, and coils under spring tension between said notch and loop.

6. A lifting jack as set forth in claim 1 in which said yielding memberincludes a notched block; a projection on the holding pawl adapted tocoact with the notch of said block but disengaged therefrom during thelifting operation; and means for forcing said projection into the notchof said block and retaining it therein during the lowering of the load.Y

j 7. A lifting jack as set forth in claim 1 in which said yieldingmember includes a coiled spring and a notched block mounted on the upperend of said spring and having a slotted'upper end; a projection on saidholding p awl adapted to be forcedinto the notch of said block butdisengaged therefrom during the lifting operation; a reversing shaftextending through said slot; and spring controlled mechanism coactingwith said shaft for forcing said projection into the notch of said blockand retaining it therein during the lowering of the load.

8. A lifting jack as set forth in claim 1 in which said yielding memberincludes a coiled spring and a notched block mounted on the upper end ofsaid spring and having a slotted upper end; a projection on said holdingpawl adapted to be forced into the notch of said block but disengagedVtherefrom during the lifting operation; a reversing shaft extendingthrough said slot; an expansible spring surrounding said shaft andbearing against said slotted end; means foi retaining said spring undercompression during the liftingA operation; and means for releasing saidspring and retaining it expanded during the lowering of the load. V

9. A lifting jack as set forth in claim Y1 in which said yielding memberincludes a coiled spring and a notched block mounted on the upper end ofsaid spring and having a slotted upper end; a projection on said holdingpawl adaptedrto be forced into the notch of said block but disengagedtherefrom during the lifting operation; an oscillatory reversing shaftextending through said slot; an expansible spring surrounding said shaftand bearing against one side of said slotted end; means at one end ofsaid shaft for moving it forward and locking it in adjusted position;and means on the opposite end of said shaft and bearing against saidforked end adapted to compress said spring during the forward movementof the shaft.

10. A lifting jack as set forth in claim 1 in which said yielding memberincludes a coiled spring and a notched block mounted on the upper end ofsaid spring and having a slotted upper end; a projection on said holdingpawl adapted to be forced into the notch of saidblock but disengagedtherefrom during the lifting operation; an oscillatory and reciprocablereversing shaft extending through said fork; an expansible springsurrounding said shaft and bearing against one side of said slotted end;a collar secured to the rear end of said shaft; a buffer spring betweensaid collar and the opposite side of said slotted end; and a cam leveron the forward end of said shaft for moving it forward to compress thespring during the lifting operation and to subsequently release saidspring permitting it to exp-and and force the projectionA of the holdingpawl into the notch of said block and retain it in engagement therewithduring the lowering of the load.

11. A ratchet lifting jack consisting of a vertically movable rackhaving a plurality of rack f' teeth; a lifting pawl; a holding pawl; aprojection on the side of each pawl; means for oscillating said liftingpawl; a yielding member pivotally mounted on the projection of thelifting pawl and movable therewith and provided with a notch near itsupper end to receive the projection of the holding pawl therebyproviding a connection between said pawls and causing them toalternately engage the rack teeth during the lowering of the load; andmeans for controlling the engagement and disengagement of saidprojection with the notch of said yielding member.

12. A lifting jack as set forth in claim 11 in which the projection onthe holding pawl has a diameter slightly less than` the width of saidnotch.

13. A ratchet lifting jack consisting of a vertically movable rackhaving a plurality of rack teeth; a lifting pawl; a holding pawl; aprojecltion on the side of each pawl; means for oscillating said liftingpawl; a yielding member pivotally mounted on the projection of thelifting pawl and movable therewith, said yielding member having near itsupper end a notch with parallel sides adapted to receive the projectionon said holding pawl; and means for retaining said holding-pawlprojection in said notch during the lowering of the load.

14. A lifting jack as set forth in claim 13 in which the means forretaining said holdingpawl projection in said notch includes an ex-Ipansible spring.

15. A lifting jack as set forth in claim 13 in which an 4expansiblespring is provided to force said holding-pawl projection into said notchand retain it in said notch during the lowering of the load; and meansfor locking said spring under compression during the lifting of theload.

16. A lifting jack as set forth in claim 13 in which said yieldingmember has a slotted upper end; a projection on said holding pawladapted to be forced into said notch but is disengaged therefrom duringthe lifting operation; a reversing shaft extending through said fork;and spring controlled mechanism on said shaft for forcing saidholding-pawl projection into the notch of said block and retaining it inengagement therewith during the lowering of the load.

17. A ratchet lifting jack consisting of a vertically movable rackhaving a plurality of rack teeth; a lifting pawl; a holding pawl; aprojection on the side of each pawl; means for oscillating said liftingpawl; a yielding member supported on said lifting pawl and during thelifting operation movable therewith independently of the holding pawl;and reversing means operable to connect the upper end of said yieldingmember with the projection of the holding pawl during the lowering ofthe load.

18. A ratchet lifting jack as set forth in claim 17, in which a casingenclosing said mechanism has three fiat sides free from obstructionwhereby a lifting chain supported by the head of `said rack may be usedon either of said sides.

FRANK L. GORMLEY.

